Iran Air flight 277, a Boeing 727, crashed while on approach to Urmia, Iran , killing 78 occupants; 27 survived the accident. Flight IR277 took off from Tehran-Mehrabad Airport at 18:33 local time (15:03 UTC) and continued its route via UL125 and G781 towards Urmia. At 15:37 UTC, after coordinating with Tehran Control Center for an approach to Urmia Airport, the aircraft began to descend and at 15:42 UTC contacted the Urmia Tower and was cleared for the TUBAR2A procedure and a VOR/DME/ILS approach to runway 21. Weather at the airport was poor with a visibility of about 800 m in heavy snow. During the execution of the approach procedure to land at Urmia Airport, the aircraft’s stick shaker (stall warning) was activated due to the low speed in relation to the flap settings. The problem was resolved after corrective action was taken. At 15:54:49 UTC, the Urmia Tower controller requested the position of flight IR277 three times. Then, the flight reported its position as being 5 miles away. The Urmia Tower controller then inquired if the aircraft was established on the ILS, to which the flight responded negatively. The Urmia Tower controller then asked the flight if it intended to continue its approach for landing. In response, flight IR277 reported that it had abandoned the approach and was performing a missed approach. The controller then requested that the flight rejoin the IAF (Initial Approach Fix) for runway 21, and flight IR277 confirmed this. After the missed approach at 16:00:41 UTC, despite being at an altitude of 8,768 feet, with a pitch-up angle of 8.1 degrees and a left bank angle of 26 degrees, the aircraft, with a speed of 170 knots (within the operational limit) and flaps set at 50 degrees, experienced a second stick shaker activation and a decrease in altitude, indicating the aircraft was approaching the stall speed threshold. This possibly occurred due to a aerodynamic change in the aircraft, potentially due to ice formation on parts of the aircraft, such as the tail section, which lacks an anti-ice system, which led to an increase in stall speed. The engine pressure ratio (EPR) of all three engines increased from (1.30 – 1.25 – 1.36) to (1.46 – 1.48 – 1.53) and then decreased over four seconds to (1.05 – 1.07 – 1.06). This could have been caused by disturbed airflow entering the engines, combined with the increase in bank angle from 26 to 40 degrees to the left, likely due to the stall. To recover from the stall, at 16:00:50 UTC, the pilot instructed for maximum power to be applied to all three engines. Initially, engine 3 reached an EPR of 2.14 at 16:00:53 UTC. However, due to disturbed airflow entering the engine, the EPR dropped, leading to engine failure. Five seconds later, engine 1 also failed in a similar manner. At 16:00:53 UTC, the Urmia Tower controller asked for the position of flight IR277 again. The flight responded with “Standby.” The tower controller then asked for the flight’s intentions, and the response was that they were abandoning the approach. Due to intermittent radio communication, the tower controller requested a repetition of the last transmission. Flight IR277 then stated, “We are going to Tehran.” At 16:01:07 UTC, the pilot ordered maximum engine power. Only engine 2 responded, reaching an EPR of 2.11. The flaps were then retracted, leading to a quicker loss of altitude. At 16:01:08 UTC, in a radial of 150 degrees from the VOR and at a distance of 30 kilometers from the airport, near the villages of Meshkabad Olya and Hasanlu, the aircraft impacted terrain and broke up. Main Cause of the Accident: The main cause of the accident was the unfavorable and abnormal conditions experienced by the aircraft, combined with inadequate handling by the cockpit crew in response to the emerging situation. Contributing Factors: – The outdated technology of the aircraft’s systems. – The lack of a suitable simulator for adverse weather conditions. – Failure to properly follow operational procedures by the flight crew. – Inadequate cockpit management (CRM).